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.TH EXIV2 1 "November 02, 2022"
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.SH NAME
exiv2 \- Image metadata manipulation tool
.SH SYNOPSIS
.B exiv2
[\fIoptions\fP] [\fIaction\fP] \fIfile\fP ...
.br
.SH DESCRIPTION
.PP
.\" TeX users may be more comfortable with the \fB<whatever>\fP and
.\" \fI<whatever>\fP escape sequences to invode bold face and italics,
.\" respectively.
.B exiv2
is a program to read and write Exif, IPTC, XMP metadata and
image comments and can read many vendor makernote tags. The program
optionally converts between Exif tags, XMP properties and IPTC
datasets as recommended by the Exif Standard, the IPTC Standard,
the XMP specification and Metadata Working Group guidelines.
.br
The following image formats are supported:
.TS
lB lB lB lB lB lB
_	_	_	_	_	_
l l l l l l.
Type	Exif	IPTC	XMP	Image Comments	ICC Profile
ARW	Read	Read	Read	-	-
AVIF	Read	Read	Read	-	-
BMP	-	-	-	-	-
CR2	Read/Write	Read/Write	Read/Write	-	Read/Write
CR3	Read	Read	Read	-	Read
CRW	Read/Write	-	-	Read/Write	-
DNG	Read/Write	Read/Write	Read/Write	-	Read/Write
EPS	-	-	Read/Write	-	-
EXV	Read/Write	Read/Write	Read/Write	Read/Write Read/Write
GIF	-	-	-	-	-
HEIC	Read	Read	Read	-	-
HEIF	Read	Read	Read	-	-
JP2	Read/Write	Read/Write	Read/Write	-	Read/Write
JPEG	Read/Write	Read/Write	Read/Write	Read/Write	Read/Write
JPEG XL	Read	Read	Read	-	-
MRW	Read	Read	Read	-	-
NEF	Read/Write	Read/Write	Read/Write	-	Read/Write
ORF	Read/Write	Read/Write	Read/Write	-	-
PEF	Read/Write	Read/Write	Read/Write	-	Read/Write
PGF	Read/Write	Read/Write	Read/Write	Read/Write	Read/Write
PNG	Read/Write	Read/Write	Read/Write	Read/Write	Read/Write
PSD	Read/Write	Read/Write	Read/Write	-	-
RAF	Read	Read	Read	-	-
RW2	Read	Read	Read	-	-
SR2	Read	Read	Read	-	-
SRW	Read/Write	Read/Write	Read/Write	-	-
TGA	-	-	-	-	-
TIFF	Read/Write	Read/Write	Read/Write	-	Read/Write
WEBP	Read/Write	-	Read/Write	-	Read/Write
XMP	-	-	Read/Write	-	-
.TE
.IP \(bu 2
Support for GIF, TGA and BMP images is minimal: the image format is
recognized, a MIME type assigned to it and the height and width of the
image are determined.
.IP \(bu 2
Reading other TIFF-like RAW image formats, which are not listed in the
table, may also work.
.IP \(bu 2
Support for BMFF file types such as CR3, HEIF, HEIC, AVIF, and 
JPEG XL is a build option. To check if this is enabled, use: 
.PP
.in +4n
.EX
$ exiv2 --version --verbose | grep bmff
enable_bmff=1
.EE
.in
.PP
.IP \(bu 2
Naked codestream JPEG XL files do not contain Exif, IPTC, or XMP metadata.
.SH ACTIONS
The \fIaction\fP argument is only required if it is not clear from the
\fIoptions\fP which action is implied.
.TP
.B pr | print
Print image metadata. This is the default action, i.e., the command
\fIexiv2 image.jpg\fP will print a summary of the image Exif metadata.
.TP
.B ex | extract
Extract metadata to *.exv, XMP sidecar (*.xmp) and thumbnail image files.
Modification commands can be applied on-the-fly.
.TP
.B in | insert
Insert metadata from corresponding *.exv, XMP sidecar (*.xmp) and
thumbnail files.  Use option \fB\-S\fP \fI.suf\fP to change the suffix
of the input files. Since files of any supported format can be used as
input files, this command can be used to copy the metadata between
files of different formats. Modification commands can be applied
on-the-fly.
.TP
.B rm | delete
Delete image metadata from the files.
.TP
.B ad | adjust
Adjust Exif timestamps by the given time. Requires at least one of the
options \fB\-a\fP \fItime\fP, \fB\-Y\fP \fIyrs\fP, \fB\-O\fP
\fImon\fP or \fB\-D\fP \fIday\fP.
.TP
.B mo | modify
Apply commands to modify (add, set, delete) the Exif, IPTC and XMP
metadata of image files. Requires option \fB\-c\fP, \fB\-m\fP or
\fB\-M\fP.
.TP
.B mv | rename
Rename files and/or set file timestamps according to the Exif create
timestamp. Uses the value of tag Exif.Photo.DateTimeOriginal or, if
not present, Exif.Image.DateTime to determine the timestamp. The
filename format can be set with \fB\-r\fP \fIfmt\fP, timestamp options
are \fB\-t\fP and \fB\-T\fP. When no rename format is provided, 
the default is \'%Y%m%d_%H%M%S\' using definitions from \fBstrftime\fP(3).
.TP
.B fi | fixiso
Copy the ISO setting from one of the proprietary Nikon or Canon
makernote ISO tags to the regular Exif ISO tag,
Exif.Photo.ISOSpeedRatings. Does not overwrite an existing standard
Exif ISO tag.
.TP
.B fc | fixcom
Fix the character encoding of Exif Unicode user comments.  Decodes the
comment using the auto-detected or specified character encoding and
writes it back in UCS-2. Use option \fB\-n\fP to specify the current
encoding of the comment if necessary.
.br
.ne 40
.SH COMMAND SUMMARY
.sp 1
.nf
exiv2 [ opt [arg] ]+ [ act ] file ...
.sp 1
option [arg]	long option	description
-a	tim	--adjust	Modify time stamps.  [+|-]HH[:MM[:SS[.mmm]]]
-b		--binary	This option is obsolete and should not be used.  Reserved for test suite (with option -pC)
-c	txt	--comment	JPEG comment string to set in the image ('modify' action).  ...
-d	tgt	--delete	Delete target(s) for the 'delete' action. ...
-D	+-n	--days	Time  adjustment by a positive or negative number of days ...
-e	tgt	--extract	Extract target(s) for the 'extract' action.
-f		--force	Do not prompt before overwriting existing  files ...
-F		--Force	Do not prompt before renaming files (Force rename) ...
-g	key	--grep	Only output info for this Exiv2 key
-h		--help	Display help and exit.
-i	tgt	--insert	Insert target(s) for the 'insert' action. ...
-k		--keep	Preserve file timestamps when updating files
-K	key	--key	Report key.  Similar to -g (grep) however key must match exactly.
-l	dir	--location	Location (directory) for files to be inserted or extracted.
-m	file	--modify	read commands from cmd-file
-M	cmd	--Modify	Command line for the 'modify' action. ...
-n	enc	--encode	Charset to decode Exif Unicode user comments. See: man 3 iconv_open
-O	+-n	--months	Time adjustment by a positive or negative number of months, ...
-p	mod	--print	Print report (common reports)
-P	flg	--Print	Print report (fine grained control)
-q		--quiet	Silence warnings and error messages from the Exiv2 library ...
-Q	lvl	--log	Set the log-level to 'd'(ebug), 'i'(nfo), 'w'(arning), 'e'(rror)
-r	fmt	--rename	Filename format for the 'rename' action. ...
-S	suf	--suffix	Use suffix .suf for source files for insert command.
-t		--timestamp	Set the file timestamp according to the Exif create timestamp ...
-T		--Timestamp	Only set the file timestamp according to Exif create timestamp ...
-u		--unknown	Show unknown tags ...
-v		--verbose	verbose
-V		--version	Show the program version and exit.
-Y	+-n	--years	Time adjustment by a positive or negative number of years ...
.sp 1
act		pr | ex | in | rm | ad | mo | mv | fi | fc
		print, extract, insert, delete, adjust, modify, rename, fixiso, fixcom

cmd		See "Commands" below.

flg		E | I | X | x | g | k | l | n | y | c | s | v | t | h
		Exif, IPTC, XMP, num, grp, key, label, name, type, count, size, vanilla, translated, hex

fmt		Default format is %Y%m%d_%H%M%S.

lvl		d | i | i | w | e
		debug, info, warning, error

mod		s | a | e | t | v | h | i | x | c | p | i | C | R | S | X
		summary, all, exif, translated, vanilla, hex, iptc, xmp, comment, preview,
		ICC Profile, Recursive Structure, Simple Structure, raw XMP

tgt		a | c | e | i | p | t | x | C | X | XX | -
		all, comment, exif, iptc, preview, thumb, xmp, ICC Profile, SideCar, RawXMP, stdin/out
.fi
.ne 40
.SH OPTIONS
.TP
.B \-h
Display help and exit.
.TP
.B \-V
Show the program version and exit.
.br
When \fB\-V\fP is combined with \fB\-v\fP (Verbose version), build information
is printed to standard output along with a list of shared libraries which
have been loaded into memory. Verbose version is supported on Windows
(MSVC, Cygwin and MinGW builds), macOS and Linux and is provided
for test and debugging.
.TP
.B \-v
Be verbose during the program run.
.TP
.B \-q
Silence warnings and error messages from the Exiv2 library during the
program run (quiet). Note that options \fB\-v\fP and \fB\-q\fP can be
used at the same time.
.TP
.B \-Q \fIlvl\fP
Set the log-level to 'd'(ebug), 'i'(nfo), 'w'(arning), 'e'(rror)
or 'm'(ute). The default log-level is 'w'. \fB\-Qm\fP is equivalent
to \fB\-q\fP. All log messages are written to standard error.
.TP
.B \-u
Show unknown tags (default is to suppress tags which don't have a name).
.TP
.B \-g \fIkey\fP
Only keys which match the given key (grep).
.br
Multiple \fB\-g\fP options
can be used to filter info to less keys. Example:
exiv2 -v -V -g webready -g time.
The default exiv2 command prints a "summary report" which is quite short.  When you use -g without a -pmod option, you do not get a summary report and in effect you get -g pattern -pa image ...

.nf
$ bin/exiv2 -g Date http://clanmills.com/Stonehenge.jpg
Exif.Image.DateTime                 Ascii    20  2015:07:16 20:25:28
Exif.Photo.DateTimeOriginal         Ascii    20  2015:07:16 15:38:54
Exif.Photo.DateTimeDigitized        Ascii    20  2015:07:16 15:38:54
Exif.NikonWt.DateDisplayFormat      Byte      1  Y/M/D
Exif.GPSInfo.GPSDateStamp           Ascii    11  2015:07:16
Xmp.xmp.ModifyDate                  XmpText  25  2015-07-16T20:25:28+01:00
.fi
.sp 1
You may use -pmod filters to further filter output.  For example:
.nf
$ bin/exiv2 -px -g Date http://clanmills.com/Stonehenge.jpg
Xmp.xmp.ModifyDate                           XmpText    25  2015-07-16T20:25:28+01:00
.fi
.sp 1
The option -g (--grep) applies to keys and not values.
.br
The key may finish with the optional modifier /i to indicate case insensitive.
.TP
.B \-K \fIkey\fP
Only report data for given key.
.br
Multiple \fB\-K\fP options can be used to report more than a single key.
.nf
$ exiv2 \-K Exif.Photo.DateTimeDigitized -K Exif.Photo.DateTimeOriginal \-pt R.jpg
Exif.Photo.DateTimeOriginal   Ascii    20  2011:09:18 16:25:48
Exif.Photo.DateTimeDigitized  Ascii    20  2011:09:18 16:25:48
.fi
.TP
.B \-n \fIenc\fP
Charset to use to decode Exif Unicode user comments. \fIenc\fP is
a name understood by \fBiconv_open\fP(3), e.g., 'UTF-8'.
.TP
.B \-k
Preserve file timestamps when updating files (keep). Can be used with
all options which update files. The flag is ignored by read-only
options.
.TP
.B \-t
Set the file timestamp according to the Exif create timestamp in
addition to renaming the file (overrides \fB\-k\fP). This option is
only used with the 'rename' action.
See Exif DateTime below for additional information.
.TP
.B \-T
Only set the file timestamp according to the Exif create timestamp, do
not rename the file (overrides \fB\-k\fP). This option is only used
with the 'rename' action. Note: On Windows you may have to set the TZ
environment variable for this option to work correctly.
See Exif DateTime below for additional information.
.TP
.B \-f,\-F
These options are used by the commands 'rename' and 'extract' to
determine the file overwrite policy.  These options are usually
combined with -v/--verbose to provide additional status output.
.br
.sp 1
The options --force and --Force apply to the 'rename' command.
The 'extract' command treats --force and --Force as permission to
overwrite.
.br
.sp 1
The default behaviour is to prompt the user.
.br
-f = Do not prompt before overwriting existing files.
.br
-F = Do not prompt before renaming files. Appends '_1'
('_2', ...) to the name of the new file.  For example:
.sp 1
.nf
$ curl --silent -O http://clanmills.com/Stonehenge.jpg
$ exiv2 --verbose --Force rename Stonehenge.jpg
File 1/1: Stonehenge.jpg
Renaming file to ./20150716_153854.jpg
$ curl --silent -O http://clanmills.com/Stonehenge.jpg
$ exiv2 --verbose --Force rename Stonehenge.jpg
File 1/1: Stonehenge.jpg
Renaming file to ./20150716_153854_1.jpg
.fi
.sp 1
The 'rename' command will only overwrite files when the option --force is used.  The option --Force is provided to avoid unintentional loss of valuable image files.
.sp 1
The 'extract' command will overwrite files when either --force or --Force is used.  Overwriting extracted files will not cause the loss of image files.
.br
.TP
.B \-r \fIfmt\fP
Filename format for the 'rename' action. The format string 
uses \fBstrftime\fP(3) definitions and supports the following 
keywords:
.TS
l l.
:basename:	original filename without extension
:dirname:	name of the directory holding the original file
:parentname:	name of parent directory
.TE
.sp 1
Note that the colons are part of the keyword.
.TP
.B \-a \fItime\fP
Time adjustment in the format [\-]HH[:MM[:SS]]. This option is only
used with the 'adjust' action. Examples: 1 adds one hour, 1:01
adds one hour and one minute, \-0:00:30 subtracts 30 seconds.
See Exif DateTime below for additional information.
.TP
.B \-Y \fIyrs\fP
Time adjustment by a positive or negative number of years, for
the 'adjust' action.
.TP
.B \-O \fImon\fP
Time adjustment by a positive or negative number of months, for
the 'adjust' action.
.TP
.B \-D \fIday\fP
Time adjustment by a positive or negative number of days, for
the 'adjust' action.
.TP
.B \-p \fImode\fP
Print mode for the 'print' action. Possible modes are:
.TS
l l.
s : print a summary of the Exif metadata (the default)
a : print Exif, IPTC and XMP metadata (shortcut for \-Pkyct)
e : print Exif metadata (shortcut for \-PEkycv)
t : interpreted (translated) Exif tags (\-PEkyct)
v : plain Exif tag values (\-PExgnycv)
h : hexdump of the Exif data (\-PExgnycsh)
i : IPTC datasets (\-PIkyct)
x : XMP properties (\-PXkyct)
c : JPEG comment
p : list available image previews, sorted by preview image size in pixels
C : print image ICC Profile (jpg, png, tiff, webp, cr2, jp2 only)
R : print image structure recursively (jpg, png, tiff, webp, cr2, jp2 only)
S : print image structure information (jpg, png, tiff, webp, cr2, jp2 only)
X : print "raw" XMP (jpg, png, tiff, webp, cr2, jp2 only)
.TE
.TP
.B \-P \fIflgs\fP
Print flags for fine control of the tag list ('print' action). Allows
control of the type of metadata as well as data columns included in
the print output.  Valid flags are:
.TS
l l.
E : include Exif tags in the list
I : IPTC datasets
X : XMP properties
x : print a column with the tag number
g : group name
k : key
l : tag label
n : tag name
y : type
c : number of components (count)
s : size in bytes
v : plain data value (vanilla values)
V : plain data value AND the word 'set ' (for use with exiv2 -m-)
t : interpreted (translated) human readable data
h : hexdump of the data
.TE
.TP
.B \-d \fItgt\fP
Delete target(s) for the 'delete' action. Possible targets are:
.TS
l l.
a : all supported metadata (the default)
e : Exif section
t : Exif thumbnail only
i : IPTC data
x : XMP packet
c : JPEG comment
C : ICC Profile
I : All IPTC data
.TE
.TP
.B \-i \fItgt\fP
Insert target(s) for the 'insert' action. Possible targets are the
same as those for the \fB\-d\fP option, plus an optional modifier:
.sp 1
X : Insert metadata from an XMP sidecar file <file>.xmp. The remaining
insert targets determine what metadata to insert from the sidecar
file. Possible are Exif, IPTC and XMP and the default is all of
these. Note that the inserted XMP properties include those converted
to Exif and IPTC.
.sp 1
XX: Insert "raw" XMP metadata from a sidecar (see option -pX)
.sp 1
- : Read from stdin.  This option is intended for "filter" operations such as:
.br
$ exiv2 -e{tgt}- \fIfilename\fP | xmllint .... | exiv2 -i{tgt}- \fIfilename\fP
.sp 1
Only JPEG thumbnails can be inserted (not TIFF thumbnails), and must be named \fIfile\fP\-thumb.jpg.
.TP
.B \-e \fItgt\fP
Extract target(s) for the 'extract' action. Possible targets are the same
as those for the \fB\-d\fP option, plus a target to extract preview
images and a modifier to generate an XMP sidecar file:
.br
p[<n>[,<m> ...]] : Extract preview images. The optional comma separated
list of preview image numbers is used to determine which preview images
to extract. The available preview images and their numbers are displayed
with the 'print' option \fB\-pp\fP.
.sp 1
C : Extract embedded ICC profile to <file>.icc
.sp 1
X : Extract metadata to an XMP sidecar file <file>.xmp. The remaining
extract targets determine what metadata to extract to the sidecar
file. Possible are Exif, IPTC and XMP and the default is all of these.
.sp
XX: Extract "raw" XMP metadata to a sidecar (see -pX)
.br
You may not use modify commands with the -eXX option and only XMP is written to the sidecar.
.sp 1
.B \- \fIOutput to stdout\fP (see -i tgt for an example of this feature)
.sp 1
.TP
.B \-c \fItxt\fP
JPEG comment string to set in the image ('modify' action). This option
can also be used with the 'extract' and 'insert' actions to modify
metadata on-the-fly.
.TP
.B \-m \fIfile\fP
Command file for the 'modify' action. This option can also be used
with the 'extract' and 'insert' actions to modify metadata on-the-fly.
-m- represents standard-input.
.TP
.B \-M \fIcmd\fP
Command line for the 'modify' action. This option can also be used
with the 'extract' and 'insert' actions to modify metadata on-the-fly.
The format for the commands is the same as that of the lines of a
command file.
.TP
.B \-l \fIdir\fP
Location (directory) for files to be inserted or extracted.
.TP
.B \-S \fI.suf\fP
Use suffix \fI.suf\fP for source files in 'insert' action.
.br
.ne 40
.SH COMMANDS
Commands for the 'modify' action can be read from a command file, e.g.,
.sp 1
.nf
$ exiv2 \-m cmd.txt image.jpg
.fi
.sp 1
or given on the command line, as in
.sp 1
.nf
$ exiv2 \-M"add Iptc.Application2.Credit String Mr. Smith" image.jpg
.fi
.sp 1
Note the quotes. Multiple \fB\-m\fP and \fB\-M\fP options can be combined,
and a non-standard XMP namespace registered.
.sp 1
.nf
$ exiv2 \-M"reg myprefix http://ns.myprefix.me/" \-M"add Xmp.myprefix.Whom Mr. Smith" \-M"set Exif.Image.Artist Mr. Smith" image.jpg
.fi
.sp 1
When writing Exif, IPTC and XMP metadata,
.B exiv2
enforces only a correct
metadata structure. It is possible to write tags with types and values
different from those specified in the standards, duplicate Exif tags,
undefined tags, or incomplete metadata. While
.B exiv2
is able to read
all metadata that it can write, other programs may have difficulties
with images that contain non standard-conforming metadata.
.SS Command format
The format of a command is
.sp 1
.nf
\fBset | add | del\fP \fIkey\fP [[\fItype\fP] \fIvalue\fP]
.fi
.TP
.B set
Set the \fIvalue\fP of an existing tag with a matching \fIkey\fP or
add the tag.
.TP
.B add
Add a tag (unless \fIkey\fP is a non\-repeatable IPTC key; nothing
prevents you from adding duplicate Exif tags).
.TP
.B del
Delete all occurrences of a tag (requires only a \fIkey\fP).
.TP
.B key
Exiv2 Exif, IPTC or XMP key.
.TP
.B type
Exif keys: Byte | Ascii | Short | Long | Rational | Undefined | SShort | SLong | SRational | Comment
.br
IPTC keys: String | Date | Time | Short | Undefined
.br
XMP keys:  XmpAlt | XmpBag | XmpSeq | LangAlt
.sp 1
A default \fItype\fP is used if none is explicitly given. The default
is determined based on \fIkey\fP.
.TP
.B value
The remaining text on the line is the value. It can optionally be
enclosed in single quotes ('\fIvalue\fP') or double quotes ("\fIvalue\fP").
.sp 1
The value is optional. Not providing any value is equivalent to an
empty value ("") and is mainly useful to create an XMP array property,
e.g., a bag.
.sp 1
The format of Exif \fBComment\fP values include an optional charset
specification at the beginning.  Comments are used by the tags Exif.Photo.UserComment, Exif.GPSInfo.GPSProcessingMethod
and Exif.GPSInfo.GPSAreaInformation.  Comments are stored as Undefined tags with an 8 byte encoding
definition follow by the encoded data. The charset is specified as follows:
.sp 1
[charset=Ascii|Jis|Unicode|Undefined] \fIcomment\fP
.br
charset=Undefined is the default
.sp 1
.nf
$ exiv2 -M'set Exif.Photo.UserComment charset=Ascii My photo' x.jpg
$ exiv2 -pa --grep UserComment x.jpg
Exif.Photo.UserComment         Undefined  16  My photo
$ exiv2 -pv --grep UserComment x.jpg
0x9286 Photo       UserComment Undefined  16  charset=Ascii My photo

$ exiv2 -M'set Exif.Photo.UserComment charset=Unicode \\u0052\\u006f\\u0062\\u0069\\u006e' x.jpg
$ exiv2 -pa --grep UserComment x.jpg
Exif.Photo.UserComment                       Undefined  18  Robin
$ exiv2 -pv --grep UserComment x.jpg
0x9286 Photo        UserComment                 Undefined  18  charset=Unicode Robin

$ exiv2 -M'set Exif.GPSInfo.GPSProcessingMethod HYBRID-FIX' x.jpg
$ exiv2 -pa --grep ProcessingMethod        x.jpg
Exif.GPSInfo.GPSProcessingMethod             Undefined  18  HYBRID-FIX
$ exiv2 -pv --grep ProcessingMethod        x.jpg
0x001b GPSInfo     GPSProcessingMethod       Undefined  18  HYBRID-FIX
.fi
.sp 1
The format for an IPTC \fBDate\fP value is: YYYY\-MM\-DD (year, month, day)
.sp 1
The format for an IPTC \fBTime\fP value is: HH:MM:SS (hours, minutes, seconds) and may optionally be followed by: -HH:MM or +HH:MM (hours, minutes ahead/behind UTC)
.sp 1
The format of \fBRational\fP (and \fBSRational\fP) is one of: \fBinteger | integer/integer | Fnumber | number\fP
.br
\fBRational\fP Examples:
.sp 1
.nf
$ exiv2 "-Mset Exif.Photo.MaxApertureValue 557429/62500" X.jpg
$ exiv2 "-Mset Exif.Photo.MaxApertureValue F5.6" X.jpg
.fi
.sp 1
The \fBRational\fP format Fnumber is for the convenience of setting aperture values.  Aperture values
are stored in Exif is an \fBAPEX\fP value which can be evaluated by the expression:
.sp 1
.nf
apex-value  =    log(Fnumber) * 2.0 / log(2.0)
number      = exp(apex-value * log(2.0) / 2.0)
.fi
.sp 1
The \fBRational\fP format Fnumber is valid for any \fBRational\fP, even when the key is not an Aperture.
More information about \fBAPEX\fP value is available from: http://en.wikipedia.org/wiki/APEX_system
.sp 1
The format of XMP \fBLangAlt\fP values includes an optional language qualifier:
.nf
.B lang="\fIlanguage-code\fP\fI" text\fP
.fi
.sp
The double quotes around the \fIlanguage-code\fP are optional. If no languge qualifier
is supplied, then the value of "x-default" is used. More information 
on the language format can be found at: https://www.ietf.org/rfc/rfc3066.txt
.sp 1
.nf
$ exiv2 -M'set Xmp.dc.title lang="de-DE" Euros' X.jpg
$ exiv2 -M'set Xmp.dc.title lang="en-GB" Pounds' X.jpg
$ exiv2 -M'set Xmp.dc.title lang="en-US" In God We Trust' X.jpg
$ exiv2 -M'set Xmp.dc.title lang=fr-FR Euros' X.jpg
$ exiv2 -M'set Xmp.dc.title lang=jp Yen' X.jpg
$ exiv2 -M'set Xmp.dc.title All others pay cash' X.jpg
.fi
.sp 1
To remove a language specification, set the value to '' (empty string)
.nf
$ exiv2 -M'set Xmp.dc.title lang="en-US"' X.jpg
.fi
To remove all language specifications, delete the key:
.nf
$ exiv2 -M'del Xmp.dc.title' X.jpg
.fi
To register additional XMP namespaces, combine the command with:
.nf
\fBreg\fP \fIprefix\fP \fInamespace\fP
.fi
.SS Command file format
Empty lines and lines starting with \fB#\fP in a command file are
ignored (comments). Remaining lines are commands as described above.
.br
.ne 40
.SH EXIF TAGNAMES AND VALUES
Exiv2 displays metadata tags and values.
.sp 1
The tag is a triplet of Family.Group.Tagname.  The following groups are defined for the family Exif:
.sp 1
.nf
GPSInfo      Canon           Fujifilm     NikonMe         OlympusFe7        SonyMisc2b
Image        CanonCf                      NikonPc         OlympusFe9        SonyMisc3c
Image2       CanonCs         Nikon1       NikonPreview    OlympusFi         SonyMinolta
Image3       CanonFi         Nikon2       NikonSi01xx     OlympusIp         SonySInfo1
Iop          CanonPa         Nikon3       NikonSi02xx     OlympusRd
MakerNote    CanonPi         NikonAFT     NikonSiD300a    OlympusRd2        Samsung2
MpfInfo      CanonPr         NikonAf      NikonSiD300b    OlympusRi         SamsungPictureWizard
Photo        CanonSi         NikonAf2     NikonSiD40                        SamsungPreview
SubImage1    CanonTi         NikonAf22    NikonSiD80      Sigma
SubImage2                    NikonCb1     NikonVr
SubImage3    Casio           NikonCb2     NikonWt         Sony1
SubImage4    Casio2          NikonCb2a                    Sony1Cs
SubImage5                    NikonCb3     Olympus         Sony1Cs2
SubImage6    Minolta         NikonCb4     Olympus2        Sony1MltCs7D
SubImage7    MinoltaCs5D     NikonFi      OlympusCs       Sony1MltCsA100
SubImage8    MinoltaCs7D     NikonFl1     OlympusEq       Sony1MltCsNew
SubImage9    MinoltaCsNew    NikonFl2     OlympusFe1      Sony1MltCsOld
SubThumb1    MinoltaCsOld    NikonFl3     OlympusFe2      Sony2
Thumbnail                    NikonIi      OlympusFe3      Sony2Cs
             Panasonic       NikonLd1     OlympusFe4      Sony2Cs2
Pentax       PanasonicRaw    NikonLd2     OlympusFe5      Sony2Fp
PentaxDng                    NikonLd3     OlympusFe6      SonyMisc1
.fi
.sp 1
Exiv2 supports Exif 2.2 Standard Tags.  Exiv2 also supports reading and writing manufacturer's MakerNote.  The information in Exif.Photo.MakerNote is encoded as manufacturer's sub-records.  For example, CanonCs are Camera Settings, NikonAf are Nikon Auto Focus records, NikonCb are Nikon Color Balance Records.  Every tag is defined by a unique tagId (16 bit integer) which is unique within a Group.
.sp
You can query Exiv2 groups and tags with the sample program taglist which is documented in README-SAMPLES.md
.sp
.ne 20
Exif Metadata values are defined in the Exif Standard.  All data is an array of data elements.  The Count defines the number elements in the array.  All elements in an array have the same type.
.sp 1
.nf
Type               Explanation
 1 BYTE            An 8-bit unsigned integer.
 2 ASCII           7-bit ASCII. NUL terminated.
 3 SHORT           A 16-bit (2-byte) unsigned integer.
 4 LONG            A 32-bit (4-byte) unsigned integer
 5 RATIONAL        Two LONGs. Numerator, denominator.
 7 UNDEFINED       An 8-bit byte.
 8 SSHORT          A 16-bit (2-byte) signed integer.
 9 SLONG           A 32-bit (4-byte) signed integer.
10 SRATIONAL       Two SLONGs. Numerator, denominator.
.fi
.sp
The printing flag t = translated and is intended for human use.  Scripts should never use translated values as they are localised and the format may change as Exiv2 evolves.  The printing flag v reports the values recorded in the metadata and should be used by scripts.
.ne 8
.fi
.SH Exif DateTime
.fi
An Exif DateTime string is stored as 20 ascii bytes (including trailing nul) in the format:
.sp 1
YYYY:MM:DD HH:MM:SS
.sp 1
The exiv2 command-line program options -t and -T will accept files
in which the Date has been incorrectly stored as YYYY-MM-DD.
The option -a enables the user to adjust the DateTime in the file and applies
the YYYY:MM:DD HH:MM:SS standard.
.sp 1
.ne 40
.SH CONFIGURATION FILE
Exiv2 can read an optional configuration file ~/.exiv2 on Unix systems and %USERPROFILE%\\exiv2.ini on Windows (using a Visual Studio build).  Cygwin and MinGW/msys2 follow the unix convention and use ~/.exiv2  You can determine the location of the configuration file with the command:
.br
.sp 1
.nf
$ exiv2 --verbose --version --grep config_path
exiv2 0.27.0.1
config_path=/Users/rmills/.exiv2
.fi
.sp 1
The purpose of the configuration file is to define your own lenses for recognition by Exiv2.  The configuration file is in Windows .ini format and has sections for each of the major camera manufactures canon,nikon,pentax,minolta,olympus and sony.  The lens metadata is stored as a integer called the lensID.  You can change the lens name associated with any lensID.
.br
.sp 1
.nf
$ cat ~/.exiv2
[nikon]
146=Robin's Sigma Lens  <--- The name of your lens
.fi
.sp 1
You obtain the lensID for your camera with the command:
.nf
$ exiv2 -pv --grep lens/i http://clanmills.com/Stonehenge.jpg
0x0083 Nikon3       LensType           Byte       1  14
0x0084 Nikon3       Lens               Rational   4  180/10 2500/10 35/10 63/10
0x008b Nikon3       LensFStops         Undefined  4  55 1 12 0
0x000c NikonLd3     LensIDNumber       Byte       1  146 <--- This number
0x000d NikonLd3     LensFStops         Byte       1  55
.fi
.ne 40
.SH EXAMPLES
.nf
$ exiv2 *.jpg
.fi
Prints a summary of the Exif information for all JPEG files in the directory.  The summary report is rather brief and presentation does not use the Family.Group.Tag convention.
.sp 1
If you use --grep pattern, the default becomes -pa.  See -g/grep above.
.sp 2
.nf
$ exiv2 -g Date http://clanmills.com/Stonehenge.jpg
.fi
.nf
$ exiv2 \-pi image.jpg
.fi
Prints the IPTC metadata of the image.
.sp 1
.nf
$ exiv2 rename img_1234.jpg
.fi
Renames img_1234.jpg (taken on 13\-Nov\-05 at 22:58:31) to 20051113_225831.jpg
.sp 1
.nf
$ exiv2 \-r'\:basename\:_%Y%m' rename img_1234.jpg
.fi
Renames img_1234.jpg to img_1234_200511.jpg
.sp 1
.nf
$ exiv2 \-et img1.jpg img2.jpg
.fi
Extracts the Exif thumbnails from the two files into img1\-thumb.jpg
and img2\-thumb.jpg.
.sp 1
.nf
$ exiv2 \-it img1.jpg img2.jpg
.fi
Inserts (copies) metadata from img1.exv to img1.jpg and from img2.exv
to img2.jpg.
.sp 1
.nf
$ exiv2 \-ep1,2 image.jpg
.fi
Extracts previews 1 and 2 from the image to the files image\-preview1.jpg
and image\-preview2.jpg.
.sp 1
.nf
$ exiv2 \-eiX image.jpg
.fi
Extracts IPTC datasets into an XMP sidecar file image.xmp and in the
process converts them to "IPTC Core" XMP schema.
.sp 1
.nf
$ exiv2 \-iixX image.jpg
.fi
Inserts IPTC and XMP metadata from an XMP sidecar file image.xmp into
image.jpg.  The resulting IPTC datasets are converted from the "IPTC
Core" XMP schema properties in the sidecar file to the older IPTC IIM4
format. The inserted XMP properties include those in the "IPTC Core"
XMP schema.
.sp 1
.nf
$ exiv2 \-M"set Exif.Photo.UserComment charset=Ascii New Exif comment" image.jpg
.fi
Sets the Exif comment to an ASCII string.
.sp 1
.nf
$ exiv2 \-M"set Exif.GPSInfo.GPSLatitude 4/1 15/1 33/1" \\ \-M"set Exif.GPSInfo.GPSLatitudeRef N" image.jpg
.fi
Sets the latitude to 4 degrees, 15 minutes and 33 seconds north. The
Exif standard stipulates that the GPSLatitude tag consists of three
Rational numbers for the degrees, minutes and seconds of the latitude
and GPSLatitudeRef contains either 'N' or 'S' for north or south
latitude respectively.
.sp 1
.nf
$ exiv2 \-l/tmp -S.CRW insert /data/*.JPG
.fi
Copy all metadata from CRW files in the /tmp directory to JPG files
with corresponding basenames in the /data directory. Note that this
copies metadata as is, without any modifications to adapt it to the
requirements of the target format. Some tags copied like this may not
make sense in the target image.

.SH SEE ALSO
.nf
.I https://exiv2.org/sample.html#modify
.fi
Sample command files.
.nf
.I https://exiv2.org/metadata.html
.fi
Taglists with \fIkey\fP and default \fItype\fP values.
.SH AUTHORS
.B exiv2
was written by Andreas Huggel and others.
.br
The Exiv2 project web site is https://exiv2.org.
.br
The code is hosted on GitHub at https://github.com/exiv2/exiv2
